Leaf and coil sprung axle differences

[Bigj66]

I’m sure I know the answer to this but if I do it was a while ago and I’ve forgotten it...🤷‍♂️

Apart from the length of the casings and halfshafts, spring mounts etc what are the differences between the front and rear axles from a leafer and a coiler?

What would prevent the hub assembly from a coiler being bolted to a leaf sprung axle casing? Is the casing flange bolt pattern different?

[Wytze]

Disco micky or mikey  did this.  The thread must be here somewhere.  The front axle wil get wider that way.  

[Bigj66]

Just now, Wytze said:

Disco micky or mikey  did this.  The thread must be here somewhere.  The front axle wil get wider that way.  

I did try searching and google but nothing on this particular subject came up. Isn’t the increased track due to the wider casing?

[Arjan]

Apart from the obvious, yes, the casing flange bolt pattern different.

Many Series have been given different axles and some are good, some...

A former friend ran a 109 on Nissan Patrol axles (SOA) with discs and factory lockers.

And some weird Mazda engine and autobox.

Very nice....

[Bigj66]

I just had a quick look under the 110 and can see that the tie bar is behind the axle on a coiler and in front on a leafer. Potentially there could be a clash between the bar and the spring.

Any reason why the axle flange off a coil axle couldn’t be welded to the casing of a leafer?

[Wytze]

I had a look, but can't find the tread . I think he used spacers between the series axle housing and the coiler swivel.  

[Wytze]

2 minutes ago, Bigj66 said:

I just had a quick look under the 110 and can see that the tie bar is behind the axle on a coiler and in front on a leafer. Potentially there could be a clash between the bar and the spring.

Any reason why the axle flange off a coil axle couldn’t be welded to the casing of a leafer?

Yes..  there would be.   I think snagger used wedge's betwee the axle and spring to clear those

[Bigj66]

4 minutes ago, Wytze said:

Yes..  there would be.   I think snagger used wedge's betwee the axle and spring to clear those

Yes I’ve read about that, spacing the spring on a block would bring it closer to the body and give more clearance perhaps. The tie bar would need to be shortened too.

[Wytze]

Yes,  but caster will increase aswell.  Weld up the holes in the series flanges, and set the coiler swivel to get that right again.  

[Bigj66]

4 minutes ago, Wytze said:

Yes,  but caster will increase aswell.  Weld up the holes in the series flanges, and set the coiler swivel to get that right again.  

I was thinking of either doing that or just fitting the casing flange from a coiler to the series case.

[Wytze]

That is what i did to, but then on a Salisbury. 

[Bigj66]

1 minute ago, Wytze said:

That is what i did to, but then on a Salisbury. 

Is the casing cast iron and if so how easy is it to weld the steel flange to it? I wouldn’t be doing that myself but just so I know what to expect from the welder.

[Wytze]

The tubes are steel,  salisbury 80 x 8 mm 

[Bigj66]

Although looking at the flange on the series axle there’s plenty of space between the bolts so it might turn out that most of the holes for the coil swivel flange can be redrilled with just the odd one needing to be filled with weld beforehand. I won’t know until I get a coil swivel flange to compare it with.

[Snagger]

1 hour ago, Wytze said:

Yes..  there would be.   I think snagger used wedge's betwee the axle and spring to clear those

No.  The geometry was set by the diff housing, in the end.  I’ll mention it in a separate answer that wraps up the more general question.

[Snagger]

2 hours ago, Bigj66 said:

I’m sure I know the answer to this but if I do it was a while ago and I’ve forgotten it...🤷‍♂️

Apart from the length of the casings and halfshafts, spring mounts etc what are the differences between the front and rear axles from a leafer and a coiler?

What would prevent the hub assembly from a coiler being bolted to a leaf sprung axle casing? Is the casing flange bolt pattern different?

The axle tubes are longer and the diff housings are set further to the right.  I have been told the right hand side shaft lengths are the same as on Series axles.  I suspect that’s not accurate, but they wouldn’t be far off.

This actually determines the height of the spring saddles if you fit them to a leaf sprung vehicle, both 88 and 109 on the front axle and both axles on an 88 (due to the different spring positions on the 109 rear end, the 110 diff housing clears the suspension springs and the bump stop cast into the Salisbury diff is in the correct place).

The cooler front axles have an inclined diff.  The track rod passes underneath and initially looks like it may be a defining requirement for the spring saddles to keep it clear of the tops of the springs.  However, because the diff is sited so much further to the right, the diff housing has to be recessed into the right spring saddle, and with the swivel pin castor angle at the correct 3 degrees (as per Series axles and all Defender, RRC and Discovery 1 models), with the diff housing just exposed at the inboard edge of the saddle, so the saddle face is flush with the neck of the diff housing where they meet, you have minimum height saddles but good track rod clearance.

It would be possible swap or modify axle flanges to swap swivel housings, but that brings in all sorts of use with steering rods, if you’re putting Defender swivels on a Series axle - the diff will be in the way of the track rod.  Fitting a track rod up front in that scenario has been done by using LHD and RHD near side swivels to have arms up front and then connecting the drag link to the track rod, but that reverses Ackerman angles and is rubbish.

 

[Bigj66]

25 minutes ago, Snagger said:

The axle tubes are longer and the diff housings are set further to the right.  I have been told the right hand side shaft lengths are the same as on Series axles.  I suspect that’s not accurate, but they wouldn’t be far off.

This actually determines the height of the spring saddles if you fit them to a leaf sprung vehicle, both 88 and 109 on the front axle and both axles on an 88 (due to the different spring positions on the 109 rear end, the 110 diff housing clears the suspension springs and the bump stop cast into the Salisbury diff is in the correct place).

The cooler front axles have an inclined diff.  The track rod passes underneath and initially looks like it may be a defining requirement for the spring saddles to keep it clear of the tops of the springs.  However, because the diff is sited so much further to the right, the diff housing has to be recessed into the right spring saddle, and with the swivel pin castor angle at the correct 3 degrees (as per Series axles and all Defender, RRC and Discovery 1 models), with the diff housing just exposed at the inboard edge of the saddle, so the saddle face is flush with the neck of the diff housing where they meet, you have minimum height saddles but good track rod clearance.

It would be possible swap or modify axle flanges to swap swivel housings, but that brings in all sorts of use with steering rods, if you’re putting Defender swivels on a Series axle - the diff will be in the way of the track rod.  Fitting a track rod up front in that scenario has been done by using LHD and RHD near side swivels to have arms up front and then connecting the drag link to the track rod, but that reverses Ackerman angles and is rubbish.

 

I’m a little confused here. How will the track rod interfere with the diff as it will pass under it as in this picture won’t it? I can see that the track rod may clash with the leaf spring but that can be addressed with suitable spacers I believe.

My thoughts are to weld up the series axle flanges and have them re-drilled to suit the coil hub assembly bolt pattern with the correct diff nose inclination. I could then get a new, shorter inner half shaft made for each side that would allow me to use the standard Defender or Disco 1 brake set up and more importantly, retain the CV joints for permanent 4WD. 

Fo the rear axle I would fit the stub axle flange in the same way along with the rear disc brake assembly and have shorter half shafts made up.
 

I’m not sure if I’ve missed something but thoughts and opinions on the proposal are very welcome.

 

 

[Wytze]

Get some used bits, and start playing around with a setup that you desire.   Keep strenght in mind.  

Just thinking out loud here,  when a half shaft goes..  Most of the time it's a short one, am i right?  Why not take two coiler axles and shorten them on the long axle tube?  That way you only need two bespoke halfshafts 

[Bigj66]

21 minutes ago, Wytze said:

Get some used bits, and start playing around with a setup that you desire.   Keep strenght in mind.  

Just thinking out loud here,  when a half shaft goes..  Most of the time it's a short one, am i right?  Why not take two coiler axles and shorten them on the long axle tube?  That way you only need two bespoke halfshafts 

I’m going to get some quotes for new half shafts but to be honest, by time I’ve paid someone to properly cut and shut an existing half shaft I can probably just buy a new one.

[Wytze]

Cut and shut half shafts  would not tickle me at all.   

[Snagger]

1 hour ago, Bigj66 said:

I’m a little confused here. How will the track rod interfere with the diff as it will pass under it as in this picture won’t it? I can see that the track rod may clash with the leaf spring but that can be addressed with suitable spacers I believe.

My thoughts are to weld up the series axle flanges and have them re-drilled to suit the coil hub assembly bolt pattern with the correct diff nose inclination. I could then get a new, shorter inner half shaft made for each side that would allow me to use the standard Defender or Disco 1 brake set up and more importantly, retain the CV joints for permanent 4WD. 

Fo the rear axle I would fit the stub axle flange in the same way along with the rear disc brake assembly and have shorter half shafts made up.
 

I’m not sure if I’ve missed something but thoughts and opinions on the proposal are very welcome.

 

 

If you do that, the track rod needs to go through the space occupied by the springs.  The saddles you’d need to clear the rod and springs would be very, very tall, maybe two inches or more than standard.Not only would you have a “slammed” front end, but the axle would be very close to the bump stops and would have next to no articulation.

[Snagger]

scratch my above response - I thought more about what you mean.

The track rod passes just beneath the diff pinion housing on the coolers, and that pinion is quite elevated.  On a Series axle, the pinion will be in the way of the track rod.  If you try a cranked rod to clear the diff, then it’ll foul the springs.  It can’t be done by that mix and match, the track rod is just in the wrong place.  That’s why people end up with that monstrous botch of a tack rod in front of the axle with reversed swivels, but with the Ackerman also reversed because they didn’t understand what they were doing.

[Wytze]

I must say... Going that route myself, moving the track rod to the front on coiler swivels, and a high steer pitman arm.   Did the numbers, and  got two different numbers on the  top and bottem pin on the swivel.   Top is about 2 inches off, the bottem one less then half of a inch.   But...  Pushing around a non running 109 in original setup is very heavy when it's not in a straight line.  And with the new setup, i can push it around a corner with a lot more ease.  So, in my opinion the new situation on my 109 is better then original.    

And,  on a 88 and a 109 are the same axle's.. So, the one or the other must be way off, ackerman wise.  Just like the 90 , the 110 and 127.  All on the same front axle.  

[missingsid]

Mine is near completion, just bleeding up the brakes.

Yes the flat bottom of the diff pinion clashes with the track rod, but there is enough depth in the casting to grind it out to clear.

I used wedges and a 10mm block welded together to raise the axle and LWB shackles to raise and tilt the axle to clear the spring and return the caster.

If you try to bolt a RRC ball to a Series axle the spigot will fit inside the axle but the bolts are 90deg out and there will be a gap between the two flanges. As the resulting axle will be narrower than a std Series axle I made up 25mm thick spacer for the gap with the corresponding bolt patterns for each side RRC to Series and returned the axle to std width for a Series.

I used RRC as I had them spare and they are 6 bolt not 7 as per Defender thus the bolt spacing works.

For half shafts I raided the KAM Diffs store room, they made long splined shafts for their lockers which can be cut down.

For track rods I removed the extension part of the RRC track rod and it was the correct length.

 

Re revers ackerman, there are various comments about this some well known and experienced people who say it is not a problem? Who knows.

I know of two other Series vehicles other than mine with this fix both of which are documented on this forum if you search.

 

[Daan]

Check this thread:

 

 

 

Fitting long shackles could solve the track rod issue, as well as a a slightly bend track rod.

Daan